Using the "Play" feature under "Devices" charm

So I never really used this feature, but I though I would play with it for a little bit. I first tried it with a Youtube App from the store and it worked well enough. I then tried it with iHeartRadio and it work well enough. I then tried with Xbox Music, but it wouldn't let me. Skydrive wouldn't use the feature either. It seems that all the MS apps won't use the feature.